Hierarchical information systems are used to organize items by function or theme in order to facilitate efficient locating of functions or locations. Hierarchical systems are used to organize documents into directories or folders and to organize functions into pull-down menus.
Conventionally one of two navigation systems are used to navigate through the various levels of a menu tree. By far the most popular menu navigation system is the so-called collapsing menu system which, for example, is used by many traditional personal computer applications. The distinguishing characteristics of this system are that the navigation always commences from the initial or root level and that the menu collapses back to the root level after a selection is made.
Computer software frequently includes dozens of functions. The sheer number of features makes it desirable to organize the functions into a hierarchy of categories to facilitate efficient searching. In a collapsing menu system each level in the hierarchy is presented as a level in the pull-down menu.
FIG. 1A shows a top or root level 10 of a hypothetical menu. Each level 10 of the menu provides a list of menu choices 12. Each menu choice 12 could be an end node such as a function whose selection initiates some action, or the menu choice 12 could lead (point) to another level 10 providing a further list of menu choices 12. Selection of an end node will cause the pull-down menu to collapse back to the root level.
FIG. 1B shows the pull-down menu of FIG. 1A with several levels of the hierarchical menu expanded. The menu structure of FIG. 1B collapses back to the root level shown in FIG. 1A once an end node is selected. The defining characteristic of such a conventional navigation system is that navigation is one-way, and always starts from the root level to an end node. This method of navigation becomes cumbersome if the desired function or destination is buried several levels down from the root directory.
To address this shortcoming, conventional operating systems such as Microsoft Windows® provide short-cuts in the form of pre-defined function keys or icons. Such short-cuts enable the user to directly access the desired function associated with the short-cut.
In the absence of a pre-defined short-cut, the user must resort to navigating the menu structure. The problem with the collapsing menu system is that navigation must always commence from the root level. Consequently more experienced users are unable to take advantage of their knowledge of the hierarchical structure to directly access a given level.
FIG. 2A shows a conventional path menu system 20 used to navigate through the directory structure of a disk. Similarly, FIG. 2B shows a conventional universal resource locator (URL) command 22 which operates similarly to the DOS path command of FIG. 2A. The conventional disk operating system (DOS) uses a path menu system 20 to navigate between various folders. Each folder represents a different level in the hierarchy. A given folder may contain one or more sub-folders. To access a target or destination level the user must know the path, i.e., the names of the each of the folders from the root folder to the target folder. A system 10 of displaying the contents of each folder is provided to guide the user through the hierarchy. Namely, by typing a command such as DIRECTORY (DIR) the user is provided with the contents of the present folder and the path leading to the present folder. The user may proceed to a sub-level in the hierarchy or may retrace his/her steps to a preceding level by knowing the path.
Navigation using the path menu system requires the user to memorize and enter complex hierarchical sequences. This method of navigation is time consuming not suitable for users who have not memorized the path. Moreover, this method becomes extremely cumbersome as the number of levels increases.
Accordingly, one object of the present invention is to provide a more efficient way of navigating hierarchical menu systems.